This core will provide lesioned animals and animal care for all the projects based at Massachusetts General Hospital. It will provide training in the same lesioning techniques for the project based at the University of Massachusetts, project 4. It will also provide evaluation of the quality of the lesions for all the projects. By having a single core create and evaluate the lesions, the results produced by the different projects can be directly compared to one another helping each project in the interpretation of its own results, increasing the interactions between the projects, and making the results more generalizable. Having a single group perform the lesions will increase the accuracy and reproducibility of the lesions because of the expertise that the surgeons will obtain due to extra practice.